Soil properties that determine the mortality and growth of Haloxylon aphyllum in the Aral region,Kazakhstan

Black saxaul (Haloxylon aphyllum) is a native tree species tolerant of aridity and salinity. It is planted to alleviate environmental damage due to the formation of the Aralkum desert and improve vegetation of the Aral Sea region. To investigate the environmental factors that determine seedling mortality and growth after rooting, we focused on soil properties and topographic factors in a study plot. We found that a hard clay layer that was low in hydraulic conductivity underlay accumulated sandy sediments at different depths. The soil in low seedling mortality areas was consistently sandy and low in salinity from the surface to a depth of 100 cm. In areas of high seedling mortality (75–100%), soils with a high content of silt and clay, with high salinity were detected within 100 cm depths. This suggests that accumulated sand sediment over a depth of 100 cm is required for root development. Plant height was positively correlated with depth of the hard clay layer. Significant relationships with plant height were also detected in chemical and physical properties at 80–100 cm such as electric conductivity (ECe), sodium adsorption ratio (SAR), and sand ratio. However, these properties had no significant relationship at 0–20 cm or with the relative elevation of the plot, suggesting that the subsequent growth of seedlings depends more on the sub-soil environment than on-surface conditions. The assessment of sub-soil condition is recommended to make site selection for reforestation much more reliable.     

Elevated level of microRNA-210 at the initiation of muscular regeneration in acetic acid-induced non-ischemic skeletal muscular injury in mice

The alteration in microRNA-210 level, a hypoxia-inducible microRNA, is not well known in non-ischemic tissue injury. In this study, we characterized the histopathological time course of acetic acid-induced skeletal muscle injury as a non-ischemic tissue injury model and investigated the expression of microRNA-210, hypoxia-inducible factor 1α, and growth factors using quantitative polymerase chain reaction analysis. After a single intramuscular dose of 3% (v/v) acetic acid to C57BL/6J mice, focal coagulative necrosis of muscle fibers was noted from 3 h after dosing and infiltration of F4/80 and Galectin-3 positive M2 macrophage was noted at 1 d after dosing. Muscular regeneration was initiated from 3 d, when M2 macrophage infiltration was most prominent, till 14 d after dosing. Hif1α and Hgf expression increased from 3 h onwards, and microRNA-210 level increased after 3 d after the treatment. However, no clear elevation in the levels of Igf1 or Vegf was observed. The infiltrative macrophages and regenerative muscle fibers were positive for hypoxia-inducible factor 1α, microRNA-210, and hepatocyte growth factor as assessed by immunohistochemistry or in situ hybridization. In this study, dominant infiltration of M2 macrophages at muscular necrosis and subsequent regeneration after a single intramuscular injection of acetic acid in mice were observed. The increase in hif1α level was observed just after the muscular injury in this non-ischemic tissue injury model, and the elevation in microRNA-210 level was noted at the initiation of tissue regeneration, indicating its effects on tissue protection and repair.     

The potential of organoids in toxicologic pathology: Histopathological and immunohistochemical evaluation of a mouse normal tissue-derived organoid-based carcinogenesis model

Recently, we introduced an organoid-based chemical carcinogenesis model using mouse normal tissue-derived organoids. In the present review article, the histopathological and immunohistochemical characteristics of mouse normal tissue-derived organoids and tumors derived from these organoids after their in vitro treatment with genotoxic carcinogens and injection into nude mouse are reviewed. In organoids treated in vitro with genotoxic carcinogens, we confirmed macroscopic tumorigenicity and histopathological findings, including neoplastic characteristics, such as multilayered epithelia and/or invasion of epithelia into the surrounding interstitium. In contrast glandular/cystic structures with monolayered epithelia were clearly demarcated from the surrounding Matrigel/interstitium in the untreated control groups. In addition to macroscopic tumorigenicity, these microscopic epithelial changes, which are characteristic of the early stages of carcinogenesis, are included in the requirements for carcinogenicity-positive judgement of the organoid-based carcinogenesis model. Immunohistochemistry of cytokeratins (CKs), used to determine the origin of epithelia and distribution of extraductal invasive lesions, or oncogenic kinases, which reflect molecular activation in epithelia following chemical treatment, is helpful for accurate diagnosis and molecular evaluation in the early stages of carcinogenesis. This information improves our biological understanding of organoid-based chemical carcinogenesis models.     

Characterization of Thiamin‐Binding Protein from Wheat Germ

A thiamin‐binding protein was isolated from wheat germ (Triticum aestivum). Its molecular mass was estimated as 120,000 Da consisting of two 56,000‐subunits. The protein contained a large amount of glutamine or glutamic acid (15.4 mol%), arginine (12.5 mol%), and glycine (12.0 mol%). The levels of tyrosine, methionine, tryptophan, and cysteine in the protein were low. Optimum pH for its thiamin‐binding activity was pH 8.0. It bound free thiamin specifically, not thiamin phosphates. The apparent dissociation and maximum bound values for the thiamin‐binding were 2.52 μM and 9.34 nmol/mg of protein, respectively. Properties of the thiamin‐binding protein from wheat germ were similar to those of the thiamin‐binding protein from rice seeds, but not from buckwheat, sesame, or sunflower seeds.     

Shiga toxin 2eB-transgenic lettuce vaccine: N-glycosylation is important for protecting against porcine edema disease

Porcine edema disease (ED) is a life-threatening toxemia caused by enteric infection with Shiga toxin 2e (Stx2e)-producing Escherichia coli (STEC) in weaned piglets. We previously reported that the stx2eB-transgenic lettuce 2BH strain shows potential for use as an oral vaccine candidate against ED. However, the 2BH strain expressed a hemagglutinin (HA)-tag together with Stx2eB and contained non-canonical N-glycosylation. Therefore, we developed two Stx2eB-lettuce strains, the 3 (G+) strain in which the HA-tag was removed from 2BH, and the 3 (G-) lettuce strain, in which the 73rd Asn was replaced with Ser to prevent non-canonical N-glycosylation of Stx2eB from the 3 (G+) strain. We examined the protective effect of these newly developed two strains compared with the previous 2BH strain against ED using a colostrum-deprived piglet STEC infection model. We found that the N-glycosylated 2BH and 3 (G+) strains relieved the pathogenic symptoms of ED in STEC-challenged piglets, whereas the non-glycosylated 3 (G-) strain did not. N-Glycosylation of the Stx2eB product in lettuce may be involved in the immune response in piglets.     

Molecular cloning and gene expression of two cytochrome P450s from permethrin-resistant Culex quinquefasciatus larvae

As part of a continuing study of factors influencing the development of pesticide resistance in insects, two new cytochrome P450s of the CYP6 family have been identified.     

Emamectin benzoate as a candidate for a trunk‐injection agent against the pine wood nematode,Bursaphelenchus xylophilus

In order to develop an effective trunk‐injection agent against pine wood nematode, Bursaphelenchus xylophilus, an in vitro assay was used to examine the antinematodal activity of 58 commercially available compounds with known modes of action. Among compounds tested, the GABA receptor agonists had better anti‐nematodal activity than compounds influencing glutamate, N‐methyl‐D ‐aspartate, β‐adrenergic, dopamine, muscarinic acetylcholine and nicotinic acetylcholine receptors, as well as those inhibiting acetylcholinesterase, monoamine oxidase, 5‐hydroxytryptamine uptake and Ca²⁺, K⁺, Na⁺ and Cl⁻ channels. Avermectins and milbemycins strongly inhibited propagation of the nematode. Emamectin benzoate proved to be the most active (IC₉₅ 0.050 µM ) being over 140 times more active than the active ingredient of conventional trunk‐injection agents. It is concluded that emamectin benzoate is a strong candidate for an anti‐nematodal trunk injection agent. © 2000 Society of Chemical Industry     

A New Binding Model for Structurally Diverse ALS Inhibitors

Acetolactate synthase (ALS) has been a very attractive target for herbicides for the last decade. There are several ALS inhibitors in commercial use spanning the world-wide market. In this study, the common structural features within a subset of ALS inhibitors were investigated by molecular graphics and quantum chemical calculations. Satisfactory results were obtained with model calculations based on the presumption that the relative location of the inhibitor azine moiety and some receptor cationic group remained fixed. The cationic group was assumed to interact with an acidic group in each of the inhibitors. This model explains many aspects of ALS inhibitors (sulfonylureas, triazolopyrimidines, pyrimidyl ethers and other classes) such as: (1) the common structural feature among the different classes of ALS inhibitors, (2) the substituent effects in the hydrophobic moiety of each class and (3) the structure–activity relationships of the acidic moiety of each class. These are significant achievements for a model based on in-vivo herbicidal activity and gas-phase calculations, but the model also has its limitations: (1) Only compounds with acidic groups and azine moieties can be addressed, (2) the structure–activity relationships of the hydrophobic moiety are not yet fully understood and (3) only a qualitative prediction of activity levels is possible. A preliminary trial of ligand design predicted the novel skeleton of an ALS inhibitor that was published independently from this study.     

Improvement in the feeding activity, early growth and survival of Pacific bluefin tuna Thunnus orientalis larvae fed a casein peptide-based microdiet supplemented with inosine monophosphate

Two feeding experiments were conducted to determine the effect of a 5′-inosine monophosphate (IMP)-supplemented casein peptide-based microdiet (MD) on the feeding activity, growth and survival of Pacific bluefin tuna (PBT) larvae. PBT larvae [total length: 14.0 mm (Exp. 1) or 13.3 mm (Exp. 2)] were fed a casein peptide-based MD supplemented with or without 3% IMP for 12 days. As a negative control, a limited number of yolk-sac larvae of spangled emperor Lethrinus nebulosus were fed only for the first 7 days and starved for the next 5 days. A sufficient amount of yolk-sac larvae of spangled emperor was fed in the Exp. 2. All fish in the control group had died by 9 or 10 days after the experiment. Extensive mortality was observed in fish fed the MD. The MD was only found in the stomach contents of PBT fed the MD + IMP. Of the fish fed an IMP-supplemented diet, 50% survived for 12 days after the initiation of both feeding experiments. In addition, significantly higher growth than that observed during the first 7 days was seen in the PBT in the IMP treatment after 12 days of the feeding experiment. These results suggest that the supplementation of casein peptide-based MD with IMP could improve the feeding activity, survival and growth performance of PBT.     

Stable isotope analysis reveals ontogenetic migration and the importance of a large mangrove estuary as a feeding ground for juvenile John’s snapper <Emphasis Type="Italic">Lutjanus johnii</Emphasis>

Stable carbon (δ¹³C) and nitrogen (δ¹⁵N) isotope ratios were measured to investigate the migration of John’s snapper Lutjanus johnii and its dependence on the food resources provided within the large Matang Mangrove Forest Reserve (40,151 ha), Malaysia. John’s snapper, and its main prey food such as penaeids, Acetes shrimps and mysids, showed generally depleted δ¹³C values in the inner mangrove area but more enriched values in the river mouth and coastal area. Some juveniles migrated into the inner mangrove areas, although they were also distributed near the river mouth areas. Isotopic signatures of snapper fish and prey reveal the ontogenetic migration of the youngest juvenile fish (<5 cm in total length) from the coastal area into the mangrove area, shifting their dependence from the coastal food web to the inner mangrove food web with their growth. The study shows the importance of the complex interconnected mangrove waterways and associated prey animals present in the large mangrove system to juvenile John’s snapper.